Going outboard from inboard.

[bernieb]

I've made my mind up ,the outdrive has got to go.But I need some advice from the (get down and get dirty mechanics).I have a 21 foot mark twain (sonic)emblem on transom a 82 year model with a 350/260hp mercruiser.I've looked at an armstrong bracket although pricey but excellent quality I have to attempt to build my own. questions..How can I compare a 225 or a 250 yamaha 2 stroke outboard for speed and will I even be able to get up on plane? My boat now is heavy and has a homemade cabin and with four guys and 75 gallons of gas ,I guess at least 4000 lbs what I have now.I get about a mile and a half to a gallon ,what on the future yama? I'm looking at a four year old engine for this project(still looking).Can you fiberglass over treated plywood?..Thanks for considering..bernie

 

[mellowyellow]

Re: Going outboard from inboard.

keep in mind an outboard will weigh less than the<br />mercruiser. glass don't like treated plywood.<br />good luck,<br />M.Y.

 

[LubeDude]

Re: Going outboard from inboard.

With that heavy of a boat, and that much horse power, you better know what you are doing when building a transome. I think I would seriously concider one allready built for your application! Im usually one that likes to build my own, but I dont think I would tackle this one.

 

[Dhadley]

Re: Going outboard from inboard.

You need to tie the transom in to the stringers too. And dont forget the transom angle. Most inboard or I/O transoms are straight so your bracket will have to pick up the desired angle.<br /><br />Good luck!